Electric signal lamp



' 1,618,741 Feb. z2, 1927. E' J. ZELT ELECTRIC SIGNAL LAMP Filed July20, 1925 Figi.

His Attorrw/y. l

...mensa Feb. zz, 1927.

u NlTEo STATES PATENT OFFICE.

ELDR J'. ZELT, 0F FORT WAYNE. INDIANA, ASSIGNOR T0 GENERAL ELECTRIC COI-PANY, A CORPORATION F NEW YORK.

ELECTRIC SIGNAL LAMP.

My invention relates to electric signal lamps and its general object isto provide an improved arrangement of lamp and mounting for usewhere thesupport for the s lamp is subject to severe shock and vibration.

The invention is particularly rapplicable in connection withelectricsignal lamps for use on railway switches where the shock andvibration from passing trains `are very great. A signal lamp is commonlymounted with part of the railway switch structure on the extended endsof two or three of the ties ,which support the'track and the vibrationfrom passing trains is extremely destructive to the lamp filament unlesssogne means is provided to absorb the vibration before reaching lthefilament. It is desirable that the lamp be designed for low Voltage asthe filament is less fragile than in a high voltage lamp and .inaccordance with the invention a transformer is provided to reduce thevoltage of the supply circuit, the mass of the transformer beingutilized to absorb shocks and vibration and reduce their destructiveeffects' on the lamp filament.

Other objects and advantages will appear from the following descriptiontaken in conf ,nection with the accompanying drawing inv which Figure 1is aside uview. of a lamp constructed 1n accordance Lwith the invention,part of the casing being broken away to reveal details of structure,Figs. 2 and 3 are.

side views of thel resiliently mounted transformer and lamp socket andFigs. 4 and 5 are views of details of the structure.

Like reference characters refer to similarY parts in the differentiigures of the drawing. In the articular lamp structure shown in thedrawl g, an outside protective casing 10 is provided in the usual way`with lenses 11 which may be of different colors to indicate the positionof a switch as the lamp is rotated with the switchoperating lever. Thecas- .lO-ismounted on a' supporting base 12 :ich is assumed to be partofsome structure such 'as a railway switch which is subject to'excessive shock and vibration.

The casing 10 is formed with a lower compartment for a transformer 13which is 5o resiliently supported by a helical spring 14.

Application filed uly 20, 1925. Serial'No. 44,695.

Two plates or disks 15 are secured to the two end turns respectively ofthe spring 14 by prongs 16 formed integrally with the plates. Thetransformer is secured to the upper plate 15 and hangs in the spacesurrounded 55 by the spring 14 and between the 'two plates The lowerplate 15 is secured to the bottom of the casinglO by screws or bolts17lwh1ch engage the plate through slots 18 1n the plate. One end offeach slot 18 is 60 enlarged to pass Iover the head of the bolt, afterwhich the plate may be rotated slightly to move the narrow end of theslot under the head of the bolt which is then tightened. The edges ofeach slot 18 at the junc- 55 ture of its narrow and enlarged portionsare turned up to form raised stops'19 so lthat 1f the bolts becomeloosened by vibration the narrow portions of the slots will be retained1n -position underr the bolt heads and the 70 plate cannot be entirelyreleased.

A plate 20 of insulating material carrying a lamp socket 21 is mountedby short posts on the upper plate 15. The partsv which'have beendescribed are of such height 75 I that a lamp 22 in the lamp socket 21is properly positloned `behind the lenses 11. The high voltage leads 23from the transformer are brought out through a suitable opening L in thecasing 10 for connection to an outside 80 source of current and the lowvoltage leads 24 are connected to the lampsocket 21 to supply currentfor the lamp 22.

The invention provides `a 'compact structure which is particularlyeffective in reventing the transmission of shock and vi ra-' tion fromthe lamp support to the lamp fila; ment and consequent rapid destructionof the ilament.

' What I claim as new and desire to secure 90 by Letters Patent of theUnited States,

1. A signal lamp including a'base, a rigidly connected transformer andlam and onsaid base and the other of said members positioned in theIspace within said helical carrying said transformer and lam spring andbetween said plates, and a lamp 3. A signal lamp includinga ase, twosecured to said transformer supporting l0 spaced plates, a helicalspring connectin plate. 5 said lates, one 'of said plates bein secure Inwitness whereof, I have hereunto Bet to said base,' a transformer secureto and my Hand this 16th da of July, 1925. supported by the other ofsaid plates and v {ILMER J. ZELT.

